The anomalous magnetic moments of the light leptons: testing the standard model with precision physics

by Dr Marc Knecht (CNRS/CPT Marseille)

Tuesday 1 Mar 2016, 14:30 → 15:30 Europe/Rome

1G09 (M.S. Angelo)

Searches for physics beyond the standard model are pursued very actively and on several fronts. While the LHC is probing the energy frontier directly and at an unprecedented level, cosmological and astrophysical observations (supernovae, CMB, galaxy survey,...) have considerably extended our knowledge at the cosmic frontier, and may give indirect indications of degrees of freedom beyond those described by the standard model. A third path that can lead to the discovery of new physics is provided by experiments that aim at probing the precision frontier, either by trying to measure observables that are suppressed in the standard model, or by looking for tiny deviations in observables that can be predicted to a very high precision. The anomalous magnetic moments of the light leptons, electron and muon, which are presently known with a relative precision at the level of 0.24 ppb and 0.54 ppm, respectively, belong to this last category. This presentation will describe both the theoretical and experimental "tours de force" that have allowed to reach such an exceptionally high precision. Experimental projects aiming at increasing this precision, and the challenges they represent for theory, will also be addressed.